Pre-splitting blasting method for joint-cutting pipe

Abstract

The invention relates to a pre-splitting blasting method for a joint-cutting pipe. The method comprises the following steps: (1) defining a peripheral profile line for a blasting excavation region, and arranging a micro-difference blasting hole in a main body blasting excavation region; (2) arranging a pre-splitting blasting hole along the peripheral profile line in the blasting excavation region; (3) placing the joint-cutting pipe in the pre-splitting blasting hole, and enabling two cut joints of the joint-cutting pipe to be in a plane formed by a shaft line of the pre-splitting blasting hole; (4) performing blasting charge on the joint-cutting pipe in the pre-splitting blasting hole, and arranging low section detonators; (5) performing blasting charge on the micro-difference blasting hole in the main body blasting excavation region, and arranging micro-difference blasting detonators at intervals at a position higher than the pre-splitting blasting hole by two sections; (6) blocking the micro-difference blasting hole and the pre-splitting blasting hole in the main body blasting excavation region; (7) connecting a priming network for blasting; (8) deslagging; and (9) repeating the steps (1) to (8) until completion of excavation. According to the pre-splitting blasting method provided by the invention, the pre-crack forming quality is improved and the engineering cost is decreased while the damage and cracking of a reserved rock body are reduced.

Description

Technical field [0001] The invention relates to a pre-splitting blasting method in the field of controlled blasting, in particular to a slit-cut pipe pre-splitting blasting method. Background technique [0002] The pre-split blasting method is to drill dense blast holes parallel to each other on the excavation contour line, charge explosives and detonators of the same section, and make them detonate before other blast holes. When the blasthole spacing, quantity and charge structure on the contour line When appropriate, after blasting, inter-connecting cracks or pre-cracks will be formed between each blasting hole, which separates the rock mass at the excavation site of the main body from the rock mass that needs to be retained, and then blasts the rock mass at the excavation site of the main body. The pre-cracks on the line have been formed, so the rock mass at the main excavation site will not cause damage to the retained rock mass when blasting, and the retaining rock mass wall...

AI Technical Summary

Problems solved by technology

However, this blasting method has a large number of drill holes, consumes a lot of explosives and other materials, and is labor-intensive and time-consuming, which affects work efficiency and increases project costs.

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